Cerebral ischaemia is a dynamic process triggered when an intracranial artery is acutely occluded, normally due to an embolism from the heart or from arteriolosclerotic lesions of more proximal arteries. Urgent rerouting of these arteries and early reperfusion of the cerebral tissue, neuroprotector therapies that intervene in the ischaemic cascade and prevention of recurrence are the therapeutic aims in the acute phase of ischaemic stroke. Thrombolytic treatment pursues the lysis of the dot occluding the intracranial artery. At present, the only approved thrombolytic treatment is the intravenous Recombinant Tissue Plasminogen Activator (rtPA). Its safety and efficacy within the first three hours of evolution of the ischaemic stroke have been demonstrated. Establishment of this treatment involves a profound change in the health structures and the training of the personnel responsible. The small therapeutic window and the limitations of this medicine in daily practice have led to the urgent exploration of new strategies: we review the reconsideration of exclusion criteria (especially in the elderly and in minor neurological deficits or those of rapid improvement), the widening of the therapeutic window beyond 3 hours with the selection of patients by multimodal image, the possibility of thrombolysis combined with antithrombotic drugs or with enhancement through ultrasound. We also review the new thrombolytics that are appearing and the intra-arterial thrombolysis approach and therapies of endovascular mechanical reperfusion.